After spending a bit more time, I finally realized that my OE environment was not configured properly, and that when things go wrong and you want to start over, you should not forget to delete the contents of ~/.oe - this is what fixed my problems.
Now, the build fails when creating the SD image, on the “dd” command being only able to write 2.1GB in the sd.img file before quitting and complaining about a ‘file too large’: does this ring a bell to anyone? I have setup all the loopback devices properly so that bitbake can run losetup command without problem (added myself to the ‘disk’ group), but it’s really the DD command which fails… Running the same command from the run.do_rootfs script from the command line creates the sd.img file without problem, by the way… (the command being dd if=/dev/zero of=${SDIMG} bs=$(echo ‘255 * 63 * 512’ | bc) count=444 )